*{
    padding: 0;
    margin: 0;
}
html,body{
    height: 100%;
    display: flex;
    flex-direction: column;
}
aside{
    display: flex;
    flex: 1;
}
header{
    height: 60px;
    background: red;
}
nav{
    width: 120px;
    background: palevioletred;
}
.count{
    background: seagreen;
    flex: 1;
}
a{
    display: block;
    padding: 5px 10px;
    color: aliceblue;
    font-size: 22px;
    text-decoration: none;
}